The invention relates to a radially movable bearing for a shaft of a gear in a steering system.
In gearboxes of steering systems, in particular, in rack-and-pinion gears or worm gears, shafts having driving wheels such as pinions or worms are borne in one fixed bearing and in one radially movable bearing. The movable bearing has the freedom to permit the driving wheel to roll on the driven wheel or a rack using a pressing device. The pressing device also compensates wear between the driving wheel and the driven wheel or the corresponding denticulation between the wheels. However, in order to enable low-friction adjustment of the movable bearing, in terms of design, transverse clearance should be provided, relative to the amount of freedom, between the outer ring of the movable bearing and a receiving element for the movable bearing in a gear housing of the gear. This leads to noise, in particular when the direction of rotation of the shafts changes, for instance in steering gears when there is a change in the direction of travel.
US 2004/0084865 A1 describes an electrical steering system, the actuator of which forms an electromotor having a flange-connected worm gear. A shaft that is arranged rotation-fast with a cylindrical worm in a gear housing is borne via two roller bearings as fixed bearings. In order to prevent noise from the denticulation between the cylindrical worm and the worm wheel, the publication suggests arranging an elastic coupling layer between the shaft and the cylindrical worm.
This design measure is complex in terms of production engineering and is not able to compensate wear in the denticulation.
The underlying object of the invention is to create a radially movable bearing for a shaft of a gear in a steering system, which movable bearing enables quiet operation for the entire service life of the gear.